Writing a game sprite driver

[Toni Wilen]

"Standard" debugging questions:

Have you narrowed it down to specific CPU models/accelerators or is it "all"? (does it happen with 68020/030? Only with 68040+) It isn't necessarily caused by CPU speed.

Does it happen if booted without startup-sequence/directly from floppy? (without setpatch/cpu libraries)

Missing blitter waits should be easily visible in emulation (if immediate blitter/wait for blitter are not ticked) with fastest possible CPU speed.

[mcgeezer]

Originally Posted by Toni Wilen

"Standard" debugging questions:

Have you narrowed it down to specific CPU models/accelerators or is it "all"? (does it happen with 68020/030? Only with 68040+) It isn't necessarily caused by CPU speed.

Does it happen if booted without startup-sequence/directly from floppy? (without setpatch/cpu libraries)

Missing blitter waits should be easily visible in emulation (if immediate blitter/wait for blitter are not ticked) with fastest possible CPU speed.

Hi Toni,

From the testing done to date, the game runs solid on an A1200 without an accelerator running, specifically @Nightshift tested the game and as soon as he enabled his accelerator running at 28Mhz he was able to get the game to hang.

I've always had the Blitter/Wait ticked in WinUAE so you're saying that I may be able to reproduce this if I untick it and run an A1200 config at 28Mhz - is that right?

Cheers,
McGeezer

[mcgeezer]

Originally Posted by Asman

@mcgeezer
change (mean adapt ) your blitter waits macro to

;-----------------------------------------------------------------------------
;
;in
;	a5 - _custom
;
BLITTERWAIT:	MACRO
		tst.b	dmaconr(a5)
.1\@		btst	#6,dmaconr(a5)
		bne.b	.1\@
	ENDM

;-----------------------------------------------------------------------------

This should help you.

Thanks Asman, I'll give it a try.

[Toni Wilen]

Originally Posted by mcgeezer

I've always had the Blitter/Wait ticked in WinUAE so you're saying that I may be able to reproduce this if I untick it and run an A1200 config at 28Mhz - is that right?

Yes. Both options are designed to "fix" missing blitter waits because commonly CPU speed is too fast in UAE and too many programs would break.

[mcgeezer]

Originally Posted by Toni Wilen

Yes. Both options are designed to "fix" missing blitter waits because commonly CPU speed is too fast in UAE and too many programs would break.

Great Toni. I'll try this tonight.

[BastyCDGS]

Hi!

Just reading your amazing development efforts. Congratulations!

Originally Posted by mcgeezer

Thanks Apollo

There's no self modifying code or CPU timing loops.
I'll double check the blitter waits though - so a good shout.

Another thing you should check, if your code works with 32-bit memory regions.

68000/68010/68EC020 have only 24-bit address space. So if you use the upper 8 bits when adressing for something different, the code will fail on 32-bit address space.

For example, 0xC0DEDBAD will use actual address 0xDEDBAD on 24-bit address space.